CantoSub AI is an AI-powered subtitle generation platform built specifically for Cantonese-language content creators, accurately transcribing spoken Cantonese, handling Hong Kong's unique code-mixing of Chinese and English, and converting speech to written Cantonese. The platform also offers one-click translation to other languages to help creators expand their reach.
Funding
Funding not disclosed
Founders
Product
Problem
Hong Kong creators face a significant lack of support in existing auto-subtitle tools for Cantonese, which have low accuracy and cannot process the region's unique "code-mixing" of Chinese and English. This forces them to spend extensive time creating subtitles manually or abandon them entirely, reducing the accessibility and professionalism of their content.
Solution
CantoSub AI provides an AI-powered platform that automates professional-grade subtitle generation in minutes for Cantonese, Mandarin, and English, with one-click translation into other languages. The platform accurately recognizes spoken Cantonese, handles Hong Kong's distinctive code-mixing, and supports conversion from colloquial speech to written Cantonese. Users upload audio or video files, and the AI generates subtitles that can be downloaded unlimited times, with options for LLM-based written language correction, AI-generated summaries, and chapter creation. The service is accessible via a web app with cloud storage, designed as an all-in-one AI production assistant for Hong Kong creators.
Target Audience
Primary customers are individual Hong Kong content creators—including YouTubers, podcasters, and educators—as well as businesses needing professional subtitles for video content targeting Cantonese-speaking audiences.
Features
- High-accuracy Cantonese speech recognition with specialized handling of Hong Kong's code-mixed Chinese-English usage
- One-click conversion from spoken Cantonese to written Cantonese and translation into multiple languages
- Support for audio and video files up to 5GB per file, with cloud storage up to 100GB
- Custom proprietary glossary support for industry-specific terms and names
- LLM-powered one-click written language proofreading and correction (Professional and Ultra plans)
- AI-generated video summaries and chapter markers
- Direct MP4 output with burned-in subtitles
- Unlimited subtitle downloads across all paid tiers
- Enterprise API access with private cloud and on-premise deployment options